Table 1.
Summary of studies looking at miRNA expression in PC.
| Aim of the Study | Sample Type | Sample Size | Method | miRNA Expression | Main Findings | Limitations | Others | References |
|---|---|---|---|---|---|---|---|---|
| The identification of differentially expressed miRNAs in PCs compared with normal tissues | Tissue | 4 PCs 26 PAds 3 PNs |
Microarray, qPCR |
miR-296 ↓ in PCs vs. PN and PAd miR-139 ↓ in PCs vs. PN and PAd miR-503 ↑ in PCs vs. PN and PAd miR-222 ↑ in PCs vs. PN and PAd |
Global miRNA profiles correctly sorted PCs from PNs miR-296, miR-139, miR-222, and miR-503 were significantly differentially expressed between PCs and PNs PCs could be discriminated from PAds by a computed score based on the expression levels of miR-296, miR-222, and miR-503 The potential role of miR-296 as an oncosuppressor in PCs |
The small sample size analyzed in the study | All PC samples were sequenced to indicate CDC73/ HRPT2 mutations |
Cobetta et al., 2010 [55] |
| Checking if parathyroid neoplasm had a distinct miRNA signature | Tissue | 9 PCs 12 PAds 15 PHyps 4 PNs |
miRNA arrays, qPCR |
miR-126 ↓ in PCs vs. PAd miR-26b ↓ in PCs vs. PAd miR-30b ↓ in PCs vs. PAd |
miR-126, miR-26b, and miR-30b were significantly different between PAd and PC miR-126 levels were the most accurate differentiator between PC and PAd (AUC 0.776) Most miRNAs were downregulated in PCs Most miRNAs were upregulated in pHyps |
The lack of the genetic characterization of PCs The small sample size analyzed in the study |
Primary PHyp was analyzed in the study | Rahbari et al., 2011 [16] |
| An assessment of the expression of C19MC–MiR371–3 clusters in parathyroid tumors | Tissue | 15 PCs+5 matched mts 24 PAds 6 PNs |
qPCR | miR517c ↑ in PCs vs. PAds | C19MC cluster aberrations are a characteristic of PCs with respect to PAds miR-517c were the most significantly different in expression between PCs and PAds miR-517c positively correlated with serum calcium, PTH and tumor weight The copy number variations of 19q13.4 loci were associated with miR-517c up-regulation |
The small sample size analyzed in the study | The set of miRNAs was chosen according to their genomic location and biological importance PC samples were sequenced to indicate CDC73/ HRPT2 mutations |
Vaira et al., 2012 [62] |
| The verification of a group of miRNA markers in a new series of samples to explore their potential significance in PC diagnosis | Tissue | 17 PCs 41 PAds |
qPCR | miR-222 ↑ in PCs vs. PAds miR-139 ↓ in PCs vs. PAds miR-126 ↓ in PCs vs. PAds miR-30b ↓ in PCs vs. PAds miR-517c ↓ in PCs vs. PAds |
miR-139, miR-222, miR-30b, miR-517c, and miR-126 were differentially expressed between PCs and PAds The combination of miR-139 and miR-30b was the best diagnostic marker between PCs and PAds (AUC 0.888) miR-30b was negatively correlated with serum calcium, PTH and akaline phophatase |
CDC73 gene sequencing was completed in only a fraction of the PCs The diagnosis of PCs was histopathologically established, but local recurrences or metastases were not observed during follow-up |
The study design was based on the validation of nine candidate miRNA markers, identified by prior studies in a new set of PC cases from the Chinese population |
Hu et al., 2018 [12] |
| The investigation of the differences in the miRNA expression profile present in serum exosomes by comparing PC and PAd | Serum | 4 PCs 4 PAds |
NGS, qPCR |
miR-27a ↑ in PCs vs. PAds | miR-146b-5p, miR-27a-5p, miR-93-5p, miR-381-3p, and miR-134-5p were differentially expressed in PC patients The expression of exosomal hsa-miR-27a-5p was significantly different between PCs and PAds (AUC 0.8594) and it could be a valuable molecular marker for PC diagnosis |
The small sample size analyzed in the study The lack of the genetic characterization of PCs |
It is the first study investigating the serum exosomal miRNA in patients with PC | Wang et al., 2021 [34] |
| Comparing the serum miRNA expression alterations between patients with benign and malignant parathyroid tumors | Serum | 13PCs 11PAds |
qPCR | miR342-3p ↓ in PCs vs. PAds | miR-342-3p was the most promising biomarker in distinguishing patients with PC and PAd (AUC 0.888) | The found miRNA biomarker is not specific only for PC The correlation between miRNAs, calcium and PTH concentrations in the two examined groups was not excluded |
Study evaluating serum miRNA expression profiles | Krupinova et al., 2021 [47] |
Parathyroid adenoma (PAd); Parathyroid carcinoma (PC); Parathyroid hyperplasia (PHyp); Normal parathyroid glands (PN); Metastasis (Mts); Next-generation sequencing (NGS); Quantitative polymerase chain reaction (qPCR); Decrease in miRNA expression levels (↓); Increase in miRNA expression levels (↑); Area under the receiver-operating characteristic curve (AUC).